Abstract Despite a wide array of treatment options, the number of people whose acute painful back injuries progress to chronic pain states continues to grow at an alarming rate. The reasons for this rapid increase in persistent back pain-related symptoms remains unknown. However, based upon previous research, we believe that a primary cause for this failure of recovery relates to maladaptive neurophysiological changes that occur within the brain in response to low back injury and pain. Specifically, injury to the back often results in acute changes to functional movement. In the short-term these movement changes protect injured tissues and avoid further pain provocation. However, the movement adaptations may not resolve when symptoms decrease and will become maladaptive over time. They contribute to reinjury and in some cases the transition to chronic low back pain (LBP). The association between these altered trunk movement patterns and chronic LBP is strongly supported in the literature. In addition, an individual?s unconsciously acquired fear of pain can change behaviors (fear of movement) and their cognitive and emotional adaptations, can drive pain persistence and be associated with sensorimotor cortical changes. We believe that these maladaptive movement patterns are driven, in large part, by brain changes in the way sensorimotor cortical regions integrate somatosensory information. Our preliminary neuroimaging data supports our central hypothesis that, individuals with chronic LBP have altered cortical sensorimotor integration that are associated with back movements. We will use a cross-sectional design (50 chronic LBP; 50 asymptomatic individuals) and two novel neuroimaging protocols to assess differences in sensorimotor brain function (Aim 1). Our innovative fMRI protocols use direct sensory stimulation to the trunk, and trunk and pelvis movements performed in the scanner to assess sensorimotor integration. This approach allows us to capture brain activation in response to loads and stresses on both the musculoskeletal structures (e.g., muscles, joints) and sensory components (e.g., muscle spindles) of the trunk. We will also collect biomechanical data during tasks that challenge trunk posture and movement control, and clinical data related to pain, fear of movement, anxiety and depression. These measures will be used to evaluate the impact of altered sensorimotor brain function on control of trunk movements (Aim 2) and to explore the relationship between cortical systems and sensory-motor associations (conditioned fear behaviors), attention-monitoring (cognitive factors), and sensory expectations and emotional responses (acquired emotional states) (Aim 3). We expect an immediate impact of our findings on back rehabilitation programs as they will have direct implications for how back exercise and movement training is taught and practiced. Longer term impact will be realized by testing efficacy and dosing of treatment approaches for prevention of recurrence and progression to chronicity.